BTXA Could Induce Fibroblast Apoptosis and Inhibit the Expression of α-SMA and Myosin II in Scar Tissue of Rabbit Ears

Purpose This study aims to explore the effects of BTXA on the proteins that affect the contraction of fibroblasts. Moreover, the optimal dose of BTXA on hypertrophic scars has not yet been determined. The current study investigated the effect of different doses of BTXA on scar formation. Materials and Methods 18 rabbits’ ears of New Zealand rabbits were used to establish hypertrophic scar model. These wounds were divided into four groups as group B (treated with deferent dosage of BTXA), group T (treated with TAC), group S (not treated), and group C (normal skin). Fibroblast apoptosis was detected by the method of TUNEL. Collagen I, III, and TGF-β1 expression were examined by western blotting method. The immunohistochemical staining and computerized image analysis were used to measure the optical density (OD value) of positive staining of α-SMA and myosin II. Results With increasing BTXA dose, the apoptotic rates increased. Western blot showed that Collagen fibrils and TGF-β1 proteins were expressed lower with the increasing of dose of BTXA (P < 0.05). α-SMA and myosin II in Group B were significantly decreased than those in Group T (P < 0.05), moreover, more myosin II can be reduced with high concentrations of BTXA (2.0 IU). Conclusions It was shown that BTXA could induce fibroblast apoptosis and inhibit the expression of α-SMA and myosin II, which can inhibit FB contraction. It plays a positive role in the treatment of scar.